Emile Delahaye began building cars in 1894 while managing the Brethon Foundry in Tours. In 1898 he incorporated the company with investors George Morane and Leon Desmarais, moving production to a former hydraulic-machinery plant in Paris. Operations manager Charles Weiffenbach joined that year as Delahaye's managerial assistant and would effectively run the company until its closure. Chief design engineer Amedee Varlet, also hired in 1898, pioneered the V6 engine in the 1911 Type 44 — an industry first. Emile Delahaye retired in 1901 due to failing health and died in 1905; from that point the company belonged entirely to the Desmarais and Morane families.
After Delahaye's death the company withdrew from racing and concentrated on trucks and fire engines for the French government. By 1907 it was exporting designs under licence to German manufacturer Protos, and heavy commercial vehicles became the main source of income through and after the First World War.
In 1932 Madame Leon Desmarais, the majority shareholder, directed Weiffenbach to reposition Delahaye toward sportier, higher-priced cars. Jean Francois was hired as chief design engineer under Varlet, and a dedicated racing department was established. The resulting Type 134 and the record-breaking Type 138 — powered by a 3.2-litre six derived from truck components — restored the company's reputation almost immediately.
By 1935 Delahaye had won eighteen minor French sports car events and finished fifth at Le Mans. The most significant model was the Type 135, a 3.5-litre six-cylinder sports car that evolved into the short-wheelbase Type 135CS. American heiress Lucy O'Reilly Schell purchased twelve of these cars for her Ecurie Bleue amateur racing team. In 1937 Rene Le Begue and Julio Quinlin won the Monte Carlo Rally in a Delahaye, and the factory ran first and second at Le Mans that year.
Against the state-sponsored German teams of Mercedes-Benz and Auto Union, Delahaye fielded the Type 145 — a 4.5-litre V12 known as the "Million Franc Delahaye" after driver Rene Dreyfus averaged 146.56 km/h over 200 kilometres at Montlhery in 1937 to claim a French government prize. Dreyfus again beat the more powerful Mercedes-Benz W154 at Pau in 1938 by exploiting the Delahaye's superior fuel economy. A French military team won the first Algiers-to-Cape Town Rally in 1951 with a Delahaye pick-up.
Commercial success from racing enabled Delahaye to acquire rival manufacturer Delage in 1935.
The company's most important road model was the Type 135, introduced in 1935 and kept in production until 1954. Its 3.5-litre six-cylinder engine — available in single, twin, and triple carburettor configurations producing up to around 160 hp — was fitted with bodies by coachbuilders including Figoni et Falaschi and Chapron. The Type 135 formed the mechanical basis of the Grand Prix Type 145 and the postwar Type 235.
Postwar production began in 1946 with resumption of the prewar 135, as the more modern Type 175 was not yet ready. The 175 introduced thoroughly contemporary styling by industrial designer Philippe Charbonneaux, but its suspension components suffered catastrophic failures and Delahaye was forced to buy back a number of cars. The resulting reputational damage, combined with French tax penalties on engines above two litres and the postwar austerity economy, made a recovery impossible. Only 573 cars were produced in 1948; by 1952 combined Delahaye-Delage output was 41 units.
The final new model, the Type 235 of 1953, was essentially a modernised 135 with hydraulic brakes and a triple-carburettor 3.6-litre engine producing 152 hp; only 84 examples were built.
Delahaye's last hope was the Delahaye VLR, a Jeep-like light reconnaissance vehicle adopted by the French army in 1951. When the army switched to the simpler Willys Jeep produced under licence by Hotchkiss, Delahaye lost its main revenue stream. In March 1954 Delahaye and Hotchkiss merged; Hotchkiss promptly ended car production, and the combined firm was absorbed by the Brandt manufacturing group within months. Delahaye, Delage, and Hotchkiss ceased to exist as brands by 1956.
Delahaye remained entirely family-owned from incorporation in 1898 until the Hotchkiss takeover in 1954, an unusual distinction for a manufacturer of its size and longevity. The Type 135CS and T150 C SS Teardrop Coupes bodied by Figoni et Falaschi are among the most prized pre-war automobiles in existence; coachbuilt examples have sold at auction for sums well above four million US dollars. The company's brief but brilliant racing record in the late 1930s — matching the German Grand Prix teams on fuel economy and durability if not outright power — stands as one of the more remarkable chapters in French motorsport history.